In today's industrial environment, systems and equipment must perform at levels thought impossible a decade ago. Global competition is forcing industry to continuously improve process operations, product quality, yield and productivity with fewer people than ever before. Production equipment must deliver unprecedented levels of reliability, availability, and maintainability as plant managers seek ways to reduce operational and support costs and to eliminate or minimize capital investments. In short, industry must invoke new measures to improve production performance and safety while minimizing costs and extending the operational life of new and aging equipment.
Sensors and actuators are found in large numbers in every process line. Each and every one of them requires data transmission and power cabling. The use of cables in not only costly to engineer and install, it is also one of the most frequent source of failure in the process line, where a considerable amount of sensors and actuators are moving or exposed to harsh environmental conditions. Therefore, it is here, at the field device level, where problems with wires really exist for the users.
The various field buses which have found their way into most industrial applications in the last decade have not changed the situation. The sensors and actuators are still typically connected via wires in a star topology to bus concentrators, or are connected to the bus in a daisy chain configuration. However, as wires age, they can crack or fail. Inspecting, testing, troubleshooting, repairing, and replacing wires require significant time, labor, and materials. If wiring faults cause a production stoppage, costs escalate rapidly.
Fluid lines are widely used in almost every industrial facility. The fluid flow in the lines is generally controlled by means of valves. Ball valves are key elements in the fluid control, in view of their simple structure and relatively low cost. Although the term “ball valve” is used in this application, and the examples which are given all specifically relate to ball valves, the invention is not limited for use only with this type of valves, but with any type of industrial valve. It is estimated that 70 million industrial ball valves sized ½″ to 4″ were sold world wide in 2004 alone. There are many typical process facilities which have more than 1000 ball valves. Although the process operators have a very strong desire and need for monitoring ball valves, in view of the costs and complications involved in the wiring and maintenance, about 80% of the ball valves in industrial facilities remain electronically unmonitored.
The control over the process could be significantly enhanced if a remote monitoring of the status of all or most ball valves in a facility, would be provided. However, as said the installation of wired monitor box to monitor the status of each valve is very expensive. The estimated cost for each monitored wired ball valve is in the range of thousands of US dollars due to the implications to lay wires in a process line facility. The cost goes even higher when the cables of the ball valve monitoring device pass through ducts, or when they need to be protected by stainless steel coverage. Sometimes, such a stainless steel coverage protection can increase the costs by 10 times. This is the main result why the industry tends to compromise the rate of monitoring, i.e., by monitoring only a small portion of the ball valves in the facility, generally only those which are considered as critical in the process.
It is therefore an object of the present invention to provide a monitoring device for a ball valve which is of low cost.
It is still another object of the present invention to provide a monitoring device which eliminates the need for very expensive wiring and maintenance.
It is still another object of the present invention to provide a monitoring device for a ball valve which is simple to install on existing installed valves as well as on new valves and maintain them in the field.
It is still another object of the present invention to provide a monitoring device which is more reliable in comparison with the wired ball-valve monitoring devices of the prior art.
It is still another object of the present invention to provide a wireless monitoring device for a ball valve, which is capable of working and operating within a large network of similar devices.
It is still another object of the present invention to provide a wireless monitoring device for a ball valve which has low current consumption, and which therefore requires replacement of batteries relatively rarely.
It is still another object of the present invention to provide means for allowing an operator to retrieve valve device data, such as the valve identification and status, software version, configuration, valve manufacturer, maintenance information, and any stored data received during operation, and insert said device data to the valve device by means of a hand held device from a short range.
It is still another object of the present invention to provide a capability for inserting operator identification to the valve device when the manual valve is actuated.
It is still another object of the present invention to provide the option of installation and calibration of the valve device locally without the need to communicate with the control room.
It is still another object of the present invention to provide a self healing meshed wireless network which yields a very reliable wireless communication even at noisy and obstructed links.
It is still another embodiment of the present invention to provide means for verifying that a desired change in the status of a ball valve has been appropriately performed.
Other objects and advantages of the present invention will become apparent as the description proceeds.